<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <script>
        function get(url, callback) {
            var xml = new XMLHttpRequest();
            xml.onload = function () {

                callback(xml.responseText);
            }
            xml.open('get', url);
            xml.send()
        }
        get('../../bootstrap_test/da.json', (data) => {
            console.log(xml.responseText);
        })
    </script>
</body>

</html>